End face sealing type gas density monitoring device

Abstract

The utility model relates to an end face sealing type gas density monitoring device, which abandons a traditional sealing structure that an observation cover and a main cylinder body extrude a sealing ring in the radial direction, and adopts a form that the sealing ring is arranged on the end face of an annular sealing part of the main cylinder body. The observation cover tightly presses the sealing ring on the end face of the annular sealing part in the axial direction, the main barrel and the observation cover are not prone to deformation under the axial load, and therefore the sealing ring between the main barrel and the observation cover is not prone to loosening and poor sealing is not prone to occurring. Therefore, according to the end face sealed type gas density monitoring device, the sealing performance of the shell of the gas density monitoring device can be improved, and the end face sealed type gas density monitoring device is simple in structure and easy to manufacture.

Description

Technical Field

[0001] The utility model relates to the field of gas density monitoring devices used for monitoring gas density by electrical equipment, in particular to an end-face sealed gas density monitoring device suitable for high altitudes. Background Art

[0002] Gas density relays and gas density meters are widely used in power systems. They are instruments used to monitor gas density or pressure. The performance of these instruments directly affects the reliable and safe operation of their related systems. Therefore, ensuring the reliable and safe operation of these instruments has become one of people's important tasks and work. Especially in high-altitude areas, as the altitude increases, the change in atmospheric pressure will have a greater impact on accuracy. Therefore, we need the gas density monitoring device to achieve a sealed shell as a whole, to achieve complete isolation of the atmospheric pressure inside and outside the shell, and to avoid poor accuracy or oil and gas leakage.

[0003] At present, due to the poor sealing performance of the shells of these gas density monitoring devices, the internal pressure of the shells cannot maintain the set standard pressure, resulting in inaccurate measurement accuracy of the gas density monitoring device. After research and analysis, it was found that the reason for the poor sealing performance of the shell is that the rigidity of the shell structure at the sealing position of the shell is insufficient. The shell is generally a thin-walled cylindrical structure, and the sealing ring is generally coaxially arranged on the side wall of the shell. Since the shell is a thin-walled part, it is easier to deform in the radial direction, resulting in slight deformation of the sealing surface and poor sealing; the sealing effect of the shell is not good, and oil or gas leakage often occurs, which also brings errors in accuracy, causing losses to users, and in serious cases, it will affect normal use. Therefore, how to improve the sealing performance of the shell of the existing gas density monitoring device is a technical problem that needs to be solved urgently in this field. Utility Model Content

[0004] In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by the present invention is to provide an end-face sealed gas density monitoring device, which can improve the sealing performance of the housing of the gas density monitoring device.

[0005] To achieve the above-mentioned purpose, the utility model provides an end-face sealed gas density monitoring device, comprising a sealed housing, a pressure detection tube and an indicating mechanism arranged in the housing, the pressure detection tube is deformed according to the gas pressure in the tube, thereby acting on the indicating mechanism so that the indicating mechanism indicates the gas density in the pressure detection tube; an air pipe connector is connected to the housing; the air pipe connector is connected to the pressure detection tube and is used to inflate the pressure detection tube;

[0006] The shell includes a main cylinder, an observation cover and a bottom cover. The observation cover seals the opening at the top end of the main cylinder. The bottom cover is sealingly connected to the bottom end of the main cylinder. An annular sealing portion is provided at the top end of the main cylinder. The observation cover is in the shape of a disc. A sealing ring is provided between the observation cover and the end face of the annular sealing portion. The observation cover presses the sealing ring against the end face of the annular sealing portion.

[0007] Preferably, the annular sealing portion is an annular structure extending radially from the top end of the main cylinder toward the center line of the main cylinder.

[0008] More preferably, the observation hood is arranged on the outside of the main cylinder body, the sealing ring is arranged between the outer end surface of the annular sealing portion and the inner end surface of the observation hood, the top of the main cylinder body is also covered with a reinforced protective hood, the reinforced protective hood is a cylindrical structure with an opening at the bottom end, the top of the reinforced protective hood is provided with an observation port, the top of the observation hood is exposed from the observation port, the reinforced protective hood presses the observation hood against the top of the main cylinder body, and the reinforced protective hood is fixed on the main cylinder body.

[0009] Furthermore, the edge of the bottom end of the reinforced protective cover is welded or threadedly connected to the main cylinder.

[0010] Furthermore, a sealing groove is provided on the outer end surface of the annular sealing portion or the inner end surface of the observation cover, and the sealing ring is arranged in the sealing groove.

[0011] More preferably, the observation hood is arranged inside the main cylinder body, the sealing ring is arranged between the inner end surface of the annular sealing portion and the outer end surface of the observation hood, a positioning ring is provided on the inner wall of the main cylinder body, the observation hood is clamped between the sealing portion and the positioning ring, and the positioning ring presses the observation hood toward the annular sealing portion.

[0012] Furthermore, the positioning ring is welded or threadedly connected to the inner wall of the main cylinder.

[0013] Furthermore, a sealing groove is provided on the inner end surface of the annular sealing portion or the outer end surface of the observation cover, and the sealing ring is arranged in the sealing groove.

[0014] Preferably, the gas density monitoring device is a gas density meter.

[0015] Preferably, the gas density monitoring device is a gas density relay, and an alarm switch is also provided in the shell. The deformation of the pressure detection tube can drive the alarm switch to close or open; a cable connector is also connected to the shell, and the cable connector is connected to the alarm switch.

[0016] As described above, the end-face sealed gas density monitoring device involved in the utility model has the following beneficial effects: in the end-face sealed gas density monitoring device of the utility model, the traditional sealing structure of radially extruding the sealing ring between the observation cover and the main cylinder is abandoned, and the sealing ring is arranged on the end face of the annular sealing part of the main cylinder, and the observation cover presses the sealing ring on the end face of the annular sealing part along the axial direction. The main cylinder and the observation cover are not easily deformed by the axial load, so the sealing ring between the main cylinder and the observation cover is not easy to loosen and cause poor sealing. Therefore, the end-face sealed gas density monitoring device of the utility model can improve the sealing performance of the housing of the gas density monitoring device, and has a simple structure and is easy to manufacture. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a front view of the density relay, viewed from the axial direction of the housing, with the viewing cover removed.

[0018] Figure 2 A cross-sectional view of the first embodiment is shown.

[0019] Figure 3 A cross-sectional view of the second embodiment is shown.

[0020] Component number description

[0021]

[0022] DETAILED DESCRIPTION

[0023] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0024] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. The change or adjustment of the relative relationship, without substantial change of the technical content, should also be regarded as the scope of the implementation of the utility model.

[0025] Please refer to Figures 1 to 3The utility model provides an end-face sealed gas density monitoring device, comprising a sealed housing 1, a pressure detection tube 4 and an indicating mechanism 5 are arranged in the housing 1, the pressure detection tube 4 is deformed according to the gas pressure in the tube, so as to act on the indicating mechanism 5 so that the indicating mechanism 5 indicates the gas density in the pressure detection tube 4, and an air pipe connector 8 is connected to the housing 1; the air pipe connector 8 is connected to the pressure detection tube 4 and is used to inflate the pressure detection tube 4;

[0026] The shell 1 includes a main cylinder 14, an observation cover 2 and a bottom cover 3. The observation cover 2 seals the opening at the top end of the main cylinder 14. The bottom cover 3 is sealingly connected to the bottom end of the main cylinder 14. The top end of the main cylinder 14 is provided with an annular sealing portion 10. The observation cover 2 is in the shape of a disc. A sealing ring 12 is provided between the observation cover 2 and the end face of the annular sealing portion 10. The observation cover 2 presses the sealing ring 12 against the end face of the annular sealing portion 10.

[0027] In the end-face sealed gas density monitoring device of the utility model, the traditional sealing structure of radially squeezing the sealing ring 12 between the observation cover 2 and the main cylinder 14 is abandoned, and the sealing ring 12 is arranged on the end face of the annular sealing portion 10 of the main cylinder 14. The observation cover 2 presses the sealing ring 12 on the end face of the annular sealing portion 10 along the axial direction. The main cylinder 14 and the observation cover 2 are not easily deformed by the axial load, so the sealing ring 12 between the main cylinder 14 and the observation cover 2 is not easy to loosen and cause poor sealing. Therefore, the end-face sealed gas density monitoring device of the utility model can improve the sealing performance of the housing 1 of the gas density monitoring device, and has a simple structure and is easy to manufacture.

[0028] In an end-face sealed gas density monitoring device of the utility model, a sealing ring is provided between an observation hood and the end face of an annular sealing portion, a sealing groove may be provided on the end face of the annular sealing portion, the sealing ring is arranged in the sealing groove, and the sealing ring is pressed against the end face of the annular sealing portion through the observation hood; or, a sealing ring is provided between the observation hood and the end face of the annular sealing portion, wherein a sealing groove is provided on the observation hood, the sealing ring is arranged in the sealing groove, and the sealing ring is pressed against the end face of the annular sealing portion through the observation hood.

[0029] The end-face sealed gas density monitoring device of the utility model can be used for a gas density relay. When the end-face sealed gas density monitoring device of the utility model is used for a gas density relay, an alarm switch (not shown in the figure) is also provided in the shell, and the deformation of the pressure detection tube can drive the alarm switch to close or open; a cable connector is also connected to the shell, and the cable connector is connected to the alarm switch.

[0030] Gas density relays are commonly used in gas insulated switchgear (GIS). Their main function is to monitor gas density (generally the density of insulating gas such as sulfur hexafluoride (SF6) gas, and sulfur hexafluoride (SF6) gas is taken as an example below) to ensure that the equipment operates under safe and reliable conditions. The gas density relay used to monitor the density of sulfur hexafluoride (SF6) mainly includes a housing 1, a pressure detection tube 4, an indicating mechanism 5 and an alarm switch arranged in the housing 1, wherein:

[0031] The pressure detection tube 4 can generally be called a pressure detection element, a bellows, a spring metal curved tube or a Baden tube, etc. One end of the pressure detection tube 4 is connected to the trachea connector 8, the trachea connector 8 is connected to the trachea 17, the trachea 17 is connected to the sulfur hexafluoride gas chamber in the device, and the other end of the pressure detection tube 4 is blocked. In this way, the sulfur hexafluoride gas density in the pressure detection tube 4 is the same as the gas density in the sulfur hexafluoride gas chamber of the device. The pressure detection tube 4 is very sensitive to the change of the gas pressure in its inner cavity and can be expanded and contracted according to the change of the gas pressure in its inner cavity. The other end of the pressure detection tube 4 (i.e., the end of the pressure detection tube 4 blocked, in the following description, the other end of the pressure detection tube 4 is the end of the pressure detection tube 4 blocked) is connected to the indicating mechanism 5 and the alarm switch in a transmission manner. Under the action of the pressure in its inner cavity, the pressure detection tube 4 is deformed according to the gas pressure in the tube so that the other end of the pressure detection tube 4 acts on the indicating mechanism 5 so that the indicating mechanism 5 indicates the gas density in the pressure detection tube 4. The deformation of the other end of the pressure detection tube 4 can also drive the alarm switch to close or open. In order to compensate for the error caused by the ambient temperature on the deformation of the pressure detection tube 4, a temperature compensation device can also be connected to the other end of the pressure detection tube 4. The temperature compensation device generally adopts a bimetallic strip 7. The temperature compensation device can compensate for the influence of temperature changes on the gas pressure. The bimetallic strip 7 is made of two metals with different expansion coefficients. They expand and contract to different degrees when the temperature changes, thereby compensating for the influence of temperature on the pressure reading.

[0032] The indicating mechanism 5 generally includes a gear mechanism and a pointer, which are generally connected to the movement 6. The movement 6 and the pressure detection tube 4 are both installed on the same base (not shown in the figure, the base is generally fixed together with the air pipe connector 8 or the two are an integrated structure, and the base is fixed together with the shell 1 as the installation basis for related parts). The deformation and expansion and contraction movement generated at the other end of the pressure detection tube 4 is converted into the rotational movement of the pointer through the gear mechanism. Generally, the pressure detection tube 4 is connected to the temperature compensation device, and the temperature compensation device is connected to the gear mechanism. After the temperature compensation device performs temperature compensation correction on the expansion and contraction deformation of the pressure detection tube 4, the movement is transmitted to the gear mechanism. The gear mechanism converts the expansion and contraction movement of the pressure detection tube 4 into the rotational movement of the pointer. The pointer indicates the scale value on the dial of the gas density relay, indicating the current SF6 gas density.

[0033] Alarm switches generally have alarm and lockout functions. Alarm switches are also generally called micro switches, magnetic-assisted electric contacts, etc. When the gas density in the pressure detection tube is lower than the preset safety threshold, the deformation of the pressure detection tube will drive the alarm switch to trigger the alarm signal. If the gas density continues to drop to the lockout value, the deformation of the pressure detection tube will drive the alarm switch to further trigger the lockout mechanism to prevent the equipment from operating under unsafe conditions.

[0034] The basic structure and working principle of the gas density relay are prior art. Although the names of the relevant basic structures and parts are different in different existing documents, the structure, function and principle are basically the same and are all included in the density relay related to the technical solution of the utility model, and will not be further elaborated here.

[0035] The technical solution of the present utility model is further described below in conjunction with the specific implementation methods of each embodiment.

[0036] Embodiment 1:

[0037] like Figure 2 As shown, the interior of the housing 1 of the gas density relay is sealed into a sealed space, and gas of set pressure (such as air, nitrogen, sulfur hexafluoride gas, etc. at standard atmospheric pressure) can be injected into the housing 1 through the inflation port 15. After the inflation is completed, the inflation port 15 is blocked with a sealing plug 16, so that the interior of the housing 1 maintains a stable set pressure and the pressure detection tube 4 is accurately deformed according to the gas pressure in the tube without being affected by the changes in the external air pressure of the housing 1. The gas density relay is zeroed and calibrated according to the set pressure, and the air pressure inside the housing 1 is kept at the set pressure, so that the accuracy of the density relay will be higher.

[0038] like Figure 2As shown, the annular sealing portion 10 is an annular structure extending radially from the top of the main cylinder 14 toward the center line of the main cylinder 14, and the observation cover 2 is arranged on the outside of the main cylinder 14. The sealing ring 12 is arranged between the outer end surface of the annular sealing portion 10 and the inner end surface of the observation cover 2. A sealing groove 11 is provided on the outer end surface of the annular sealing portion 10 or the inner end surface of the observation cover 2, and the sealing ring 12 is arranged in the sealing groove 11. The observation cover 2 is a circular transparent sheet. The observation cover 2 is pressed on the end face of the annular sealing portion 10 to compress the sealing ring 12. In order to strengthen the strength and rigidity of the observation cover 2, a reinforced protective cover 18 is also provided on the top of the main cylinder 14. The reinforced protective cover 18 is a cylindrical structure with an opening at the bottom end. An observation port 19 is provided on the top of the reinforced protective cover 18, and the top of the observation cover 2 is exposed from the observation port 19. The reinforced protective cover 18 presses the observation cover 2 on the top of the main cylinder 14, and the reinforced protective cover 18 is fixed on the main cylinder 14. The edge of the bottom of the reinforced protective cover 18 can be welded to the main cylinder 14 by welding, or an internal thread can be provided on the inner side wall of the bottom end of the reinforced protective cover 18, and an external thread can be provided on the top of the main cylinder 14 to thread the reinforced protective cover 18 and the main cylinder 14 together. Figure 2 Since the gas density relay shown adopts the end face sealing form, the axial rigidity of the housing 1 is relatively large, the sealing position is not easy to deform, and the sealing performance is relatively good.

[0039] The end-face sealed gas density monitoring device of the utility model achieves complete isolation of the atmospheric pressure inside the shell 1 and outside the shell 1 by sealing the shell 1, thereby eliminating the influence of atmospheric pressure changes caused by different altitudes on the accuracy, and its structure is simpler and more reliable; moreover, since the air pipe connector 8, the cable connector 9 and the inflation port 15 are all arranged on the bottom cover 3, there is no need to open a hole groove structure on the side wall of the main cylinder 14 of the shell 1 to affect the structural rigidity of the main cylinder 14 of the shell 1, the rigidity of the main cylinder 14 of the shell 1 is better, and the side wall of the main cylinder 14 is not It will be pulled by parts such as the air pipe 17 or cables, so the main cylinder 14 of the shell 1 is not easy to deform, and the seal between the observation cover 2 and the main cylinder 14 is not easily affected. The sealing performance of the shell 1 is good, and the gas inside the shell 1 will not leak, and the external gas will not leak into the shell 1. The shell 1 maintains a stable set air pressure. Therefore, the pressure detection tube 4 produces accurate deformation according to the gas pressure in the tube and will not be affected by the change of the external air pressure of the shell 1. The detection accuracy of the end-face sealed gas density monitoring device of the utility model will be higher. The end-face sealed gas density monitoring device of the utility model greatly improves the reliability of the sealing performance of the shell 1 of the gas density monitoring device in terms of structure, and can effectively avoid the influence of atmospheric pressure changes on accuracy. At the same time, in the oil-filled density relay, oil leakage or air leakage can also be completely avoided.

[0040] Embodiment 2:

[0041] like Figure 3 As shown, Figure 3 The sealing part of the gas density relay is also a circular ring structure with an annular end surface arranged at the top of the main cylinder 14, and the observation cover 2 is a circular transparent sheet. Figure 2 The gas density relay structure is different in that: Figure 3 The observation hood 2 of the gas density relay is arranged on the inner side of the main cylinder 14, and the sealing ring 12 is arranged between the inner end face of the annular sealing portion 10 and the outer end face of the observation hood 2 and is clamped by the two, so as to seal the inner cavity of the shell 1. A positioning ring 13 is provided on the inner wall of the main cylinder 14, and the observation hood 2 is clamped between the sealing portion and the positioning ring 13. The positioning ring 13 presses the observation hood 2 toward the annular sealing portion 10. A sealing groove 11 is provided on the inner end face of the annular sealing portion 10 or the outer end face of the observation hood 2, and the sealing ring 12 is arranged in the sealing groove 11. In order to fix the observation hood 2, a positioning ring 13 is also provided in the inner cavity of the main cylinder 14, and the positioning ring 13 is welded or threadedly connected to the inner wall of the main cylinder 14. The observation hood 2 is clamped between the annular sealing portion 10 and the positioning ring 13. Figure 2 The gas density relay structure is different in that: Figure 3 The gas density relay in does not require a reinforced protective cover 18. Figure 3 Since the gas density relay shown adopts the end face sealing form, the axial rigidity of the housing 1 is relatively large, the sealing position is not easy to deform, and the sealing performance is relatively good.

[0042] The gas density meter is also a common gas density monitoring device. The difference between the gas density meter and the gas density relay is that the gas density meter does not need an alarm switch, and the signal connection line, cable connector and other parts corresponding to the alarm switch. The other basic structures and basic principles are the same as those of the gas density relay. The end-face sealed gas density monitoring device of the utility model can be used for the gas density meter. When the end-face sealed gas density monitoring device of the utility model is used for the gas density meter, it is the same as the gas density relay. Figures 1 to 3 The gas density relay-related structure in the figure only lacks the alarm switch (not shown) and the cable connector 9, and the rest of the structure is the same and will not be repeated here.

[0043] Based on the technical solution of the above embodiment, the sealing part of the shell of the end-face sealed gas density monitoring device of the utility model is subjected to axial extrusion, the axial rigidity of the main cylinder is strong, and it is not easy to deform at the sealing part, the seal between the observation cover and the main cylinder is not easily affected, the sealing performance of the shell is good, and the inside of the shell maintains a stable set air pressure. Therefore, the pressure detection tube produces accurate deformation according to the gas pressure in the tube without being affected by the change of air pressure outside the shell, and the detection accuracy is high. The end-face sealed gas density monitoring device of the utility model can improve the sealing performance of the gas density relay shell, has a simple structure, and is easy to manufacture.

[0044] In summary, the utility model effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0045] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.

Claims

1. An end-face sealed gas density monitoring device, comprising a sealed housing, a pressure detection tube and an indicating mechanism arranged in the housing, the pressure detection tube deforms according to the gas pressure in the tube, thereby acting on the indicating mechanism so that the indicating mechanism indicates the gas density in the pressure detection tube; an air pipe connector is connected to the housing; the air pipe connector is connected to the pressure detection tube and is used to inflate the pressure detection tube; the characteristics are: The shell includes a main cylinder, an observation cover and a bottom cover. The observation cover seals the opening at the top end of the main cylinder. The bottom cover is sealingly connected to the bottom end of the main cylinder. An annular sealing portion is provided at the top end of the main cylinder. The observation cover is in the shape of a disc. A sealing ring is provided between the observation cover and the end face of the annular sealing portion. The observation cover presses the sealing ring against the end face of the annular sealing portion.

2. The end-face sealed gas density monitoring device according to claim 1, characterized in that: The annular sealing portion is an annular structure extending radially from the top of the main cylinder toward the center line of the main cylinder.

3. The end-face sealed gas density monitoring device according to claim 2, characterized in that: The observation cover is arranged on the outside of the main cylinder body, and the sealing ring is arranged between the outer end surface of the annular sealing part and the inner end surface of the observation cover. The top of the main cylinder body is also covered with a reinforced protective cover, which is a cylindrical structure with an opening at the bottom. The top of the reinforced protective cover is provided with an observation port, and the top of the observation cover is exposed from the observation port. The reinforced protective cover presses the observation cover to the top of the main cylinder body, and the reinforced protective cover is fixed on the main cylinder body.

4. The end-face sealed gas density monitoring device according to claim 3 is characterized in that: The edge of the bottom end of the reinforced protective cover is welded or threadedly connected to the main cylinder.

5. The end-face sealed gas density monitoring device according to claim 3, characterized in that: A sealing groove is provided on the outer end surface of the annular sealing portion or the inner end surface of the observation cover, and the sealing ring is arranged in the sealing groove.

6. The end-face sealed gas density monitoring device according to claim 2, characterized in that: The observation cover is arranged inside the main cylinder body, the sealing ring is arranged between the inner end surface of the annular sealing part and the outer end surface of the observation cover, a positioning ring is provided on the inner wall of the main cylinder body, the observation cover is clamped between the sealing part and the positioning ring, and the positioning ring presses the observation cover toward the annular sealing part.

7. The end-face sealed gas density monitoring device according to claim 6, characterized in that: The positioning ring is welded on the inner side wall of the main cylinder.

8. The end-face sealed gas density monitoring device according to claim 6, characterized in that: A sealing groove is provided on the inner end surface of the annular sealing portion or the outer end surface of the observation cover, and the sealing ring is arranged in the sealing groove.

9. The end-face sealed gas density monitoring device according to claim 1, characterized in that: The gas density monitoring device is a gas density meter.

10. The end-face sealed gas density monitoring device according to claim 1, characterized in that: The gas density monitoring device is a gas density relay, and an alarm switch is also provided in the shell. The deformation of the pressure detection tube can drive the alarm switch to close or open; a cable connector is also connected to the shell, and the cable connector is connected to the alarm switch.

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